Epidemiological studies and their relevance to the clinical rheumatologist.
D000367:Age Factors; D004812:Epidemiologic Methods; D006432:Hemochromatosis / Q000150:complications; D006801:Humans; D007592:Joint Diseases / Q000150:complications; D010003:Osteoarthritis / Q000453:epidemiology; D012216:Rheumatic Diseases / Q000453:epidemiology*